For consumer satisfaction, toothpaste compositions should possess certain excellent physical properties to which the consumer is accustomed. These properties provide a toothpaste that has appealing taste, has good cleansing effect, is easy to rinse, has excellent mouth feel, and has physical stability. Toothpaste compositions with acceptable physical stability do not readily harden on the shelf and do not exhibit phase separation such as water or flavor separation. The appearance of the paste as it comes out of the dispenser is also considered important. It should appear smooth and have a pleasant sheen or glossy appearance.
These properties must be provided in a toothpaste composition that is cost effective for the consumer. There is a continuing demand to provide toothpaste compositions at lower cost while maintaining desirable properties. This is especially important in parts of the world where, despite its well-established benefits in dental hygiene, toothpaste is unaffordable.
Toothpaste compositions typically contain a polishing agent or abrasive, a humectant, a binder or thickener, a surface active agent or surfactant, and water, as well as materials that provide therapeutic or cosmetic benefits, such as fluorides, flavorings, and sweeteners. The humectant and water are also referred to collectively as the vehicle. Although the water content varies, most toothpaste compositions comprise about 10 to 25 weight percent water.
Because, compared to the cost of the other ingredients, water is relatively inexpensive, one way to lower the cost of a toothpaste composition is to increase its water content. However, in these toothpaste compositions relatively high water content often produces problems of low viscosity and/or phase separation. During storage water has a tendency to move downward and oils, such flavorings, move upward. With a high moisture toothpaste, the consumer may notice “wet cap” or flavor concentration in the tip depending on whether filled tubes were stored with the caps up or down. Phase separation may also adversely affect the sheen or gloss of the extruded toothpaste composition.
Many conventional toothpaste compositions use silica based polishing agents. However, there is a need in the industry to reduce the abrasive nature of such conventional toothpaste compositions using silica and calcium based polishing agents. Thus, a need exists for a high moisture toothpaste composition with a high moisture content, favorable physical properties, and reduced abrasivity.